How to iterate through JavaScript Maps using ng-repeat in angularjs?

I'm trying to use JavaScript Maps in ng-repeat angular's directive while searching I found that it could be done this way :

<ul ng-controller="MyCtrl">
    <li ng-repeat='(key, value) in {"First Name":"John", "Last Name":"Smith"}'>
        <span>Key: {{key}}, value: {{value}}</span>
    </li>
</ul>

but this works only with normal JSON objects, when I create a real Map the following way, it doesn't work.

I have this controller for example

function MyCtrl($scope) {
    $scope.items = new map();
    $scope.items.set('adam',{'age':10,'fav':'doogie'});
    $scope.items.set('amalie',{'age':12});
}

and this html code

<ul>
    <li ng-repeat='(key, value) in items'>
        <span>Key: {{key}}, value: {{value}}</span>
    </li>
</ul>